LOS ANGELES (Reuters) - Actor Robin Williams will undergo heart surgery for an aortic valve replacement, forcing him to cut short his stand-up comedy tour, his representative said on Thursday.

Williams, 57, was in the middle of his 80-city, one-man "Weapons of Self-Destruction" tour in Florida this week when he complained of shortness of breath. His representative did not disclose where or when his surgery would occur.

"I'm so touched by everyone's support and well wishes," Williams was quoted as saying in a statement. "This tour has been amazing fun and I can't wait to get back out on the road after a little tune-up."

Williams won an Oscar for his supporting role as a psychologist in the 1997 drama "Good Will Hunting." He is best known for a manic comedy routine steeped in wacky accents and improvisation. He spent two months in rehab in 2006 to combat a drinking problem.

The actor's older brother, Robert Todd Williams, died in 2007 of complications from heart surgery.